Hairpin exchangers

Used by permission Bui. Application and Design Estimating of Double Pipe and Hairpin Exchangers. Brown Eintube Co., A Koch Engineering Co., Houston, Texas. 

Also called "hairpin" exchangers, the double-pipe heat exchanger, as shown in Fig. 26.10, is the simplest of all types we have discussed. It is nothing more than two concentric pipes. The inner pipe might be 2 inch diameter and the outer pipe 3 in. Double-pipe exchangers are... 

U-Tube Heat Excbajiger (Fig. 11-36J) The tube bundle consists of a stationaiy tube sheet, U tubes (or hairpin tubes), baffles or support plates, and appropriate tie rods and spacers. The tube bundle can be removed from the heat-exchanger shell. A tube-side header (stationary head) and a shell with integr shell cover, which is welded to the shell, are provided. Each tube is free to expand or contract without any limitation being placed upon it by the other tubes. 

The hairpin heat exchanger, unhke the removable bundle TEMA styles, is designed for bundle insertion and removal from the return end rather than the tubesheet end. This is accomplished by means of removable spht rings which shde into grooves machined around the outside of each tubesheet and lock the tubesheets to the external closure flanges. This provides a distinct advantage in maintenance since bundle removal... 

The best known use of the hairpin is its operation in true counter-current flow which yields the most efficient design for processes that have a close temperature approach or temperature cross. However, maintaining countercurrent flow in a tubular heat exchanger usually implies one tube pass for each shell pass. As recently as 30 years ago, the lack of inexpensive, multiple-tube pass capability often diluted me advantages gained from countercurrent flow. 

Figure 10-4A(2). Multitube hairpin fintube heat exchangers. The individual shell modules can be arranged into several configurations to suit the process parallel and/or series flow arrangements. The shell size range is 3-16 in. (Used by permission Brown Fintube Co., A Koch Engineering Co., Bui. B-30-1.)...

Figure 9.64. Heat exchanger with hairpin tubes...

Haas, D. B. 203, 204, 228 Hagen, G. 78, 139 Hair hygrometer 759 Hairpin tubes, heat exchanger 505 --------exchangers 503... 

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